薄液膜蒸发传热影响因素分析

用数值方法求解了蒸发薄液膜区域的控制方程,得到了不同过热度下界面的形状和液膜内部的压力分布,计算结果显示:在蒸发薄液膜区域存在着很大的热流密度,脱离压力起到了液体输运的主导作用,表面张力系数的改变对本区域换热影响很小.毛细微槽宽度较大时(μm量级),其改变对薄液膜区域的影响也很小.选取汽化潜热较大的工质和采用降低液体黏...

Analyses of factors affecting heat transfer in evaporating thin film region

The governing equations for the evaporating thin film region were solved numerically.The profile of interface and the pressure distribution in the film were obtained under different overheat conditions.The results indicate that a very high heat flux exits in this region and disjoining pressure is the predominant force for the transport of the liquid.Surface tension does not affect heat transfer significantly.While the groove width is big(in μm dimension),its effect is small.In order to enhance heat transfer,work fluids with higher latent heat of evaporation and lower viscosity should be chosen.